1. Technical Field
The present invention relates to flip-chip technologies, and more specifically, to flip chip underfill in flip-chip technologies.
2. Related Art
In flip-chip technologies, chip solder balls are typically formed on top of a semiconductor chip and then the chip is flipped upside down and bonded to a substrate.
The difference in thermal expansion coefficients of the chip and the substrate may cause solder ball fatigue or cracking in the chip resulting in chip failure. Therefore, there is a need for a structure (and a method for forming the same) in which the difference between thermal expansion coefficients of the chip and the substrate does not cause solder ball fatigue or chip cracking as in the prior art.